Our kitchen sink vent pipe goes up through the ceiling but not through the roof, should it go through the roof?

  • Somebody here can probably quote the plumbing code, which might differ in your local area so you'll want to double-check. In general, from what I recall, vents penetrating the building must be higher than nearby windows and doors, or at least 10 feet away, and that type of thing. The idea is to prevent sewer gas from entering the dwelling. So I'm guessing that venting into the attic where you would just fill your attic with sewer gases probably isn't going to cut it. Sure, it's just the kitchen sink, but that drain is attached to the main one, and nasty gases could find their way up that vent. Feb 4 '15 at 4:49
  • Where in the world are you, as the rules can vary, along with acceptable remedies. Feb 4 '15 at 22:21

This is actually pretty easy to remedy given that you have decent attic access. You just route vent to the main stack. Might have to cut out main stack in attic, support it, add a T to connect vent and put the pieces back together. That would be easy way to code compliance and could cost as little as $30-40.


If there is a main Vent stack in the house, then just route and connect it to it. Just be sure that you have your 1/4" per foot drop from end to end. We routed all front of the house vents to a Main stack in the back of the house. The only other issue you want to be aware of is the exit main stack should be as big as the sewer exit line. so if you have a 4" sewer, your stack should be at least 4". If not you should be adding a new stack. Leaking sewer gases in the Attic is not a good thing. You can downsize the vent one size from the drain it is connected it. If combining, you would need to look up the code to get the proper sizing.

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